Passivhaus in-company training: take your team to the forefront of construction

Passivhaus in-company training: take your team to the forefront of construction At Praxis Resilient Buildings we offer specialised training for companies, tradespeople and professionals who want to deliver projects to Passivhaus standard and upskill in high-performance, sustainable construction. We design tailor-made courses, adapting them to the specific needs of each company or team to ensure …

Passivhaus in-company training: take your team to the forefront of construction

At Praxis Resilient Buildings we offer specialised training for companies, tradespeople and professionals who want to deliver projects to Passivhaus standard and upskill in high-performance, sustainable construction.

We design tailor-made courses, adapting them to the specific needs of each company or team to ensure that they are practical, applicable, and fully aligned with their objectives.

Passivhaus In-Company, forma a tu equipo en la vanguardia de la construcción
Passivhaus In-Company, forma a tu equipo en la vanguardia de la construcción

With a proven track record in Passivhaus training.

we’ve worked with universities and professional associations, and we offer online courses validated by the Passive House Institute and the Spanish Passivhaus Association, Plataforma PEP. In addition, we organise official exams for Passivhaus certified courses such as “Construction Verifier” and “Site Supervisor, add-ons to the Passivhaus Designer and Tradesperson qualifications.

We offer customized training that can address the Passivhaus standard in depth, or focus on specific aspects of sustainable construction, such as airtightness, ventilation, high-performance windows, or building services. We also design courses adapted to specific projects, ensuring that both the design and construction teams have the skills for cost-effective project delivery and for achieving certification.

We have worked with numerous companies in the construction sector, providing training to their teams based on their specific needs.

Tomas Gràcia Corporación, a construction company, entrusted us with the training of their M & E team, to install building services to Passivhaus standard in a 30-home development. The training included key concepts such as airtightness service penetrations of the thermal envelope, insulation requirements on ducts and pipes, efficient heating, cooling and hot water systems, and site supervision of services.

Wolf Group, manufacturers of sealants and adhesives, asked us for Passivhaus training for their management and sales team, with a particular focus on airtightness. We adapted our advanced training course to their product range, so they can be correctly specified on Passivhaus projects, and we even carried out a Blower Door test at their facilities, so they could see a live test and understand where and how air leaks in the building envelope occur.

Cambolico, developer and contractor, requested our training for their construction team, who had no previous experience in Passivhaus and who were about to build a multi-residential development with 14 flats, the TerrassaHaus, Barcelona, which achieved Passivhaus Classic certification.

Your course has saved me at least €20,000 in construction costs

This was the feedback we received from the CEO of Cambolico.

Passivhaus In-Company, forma a tu equipo en la vanguardia de la construcción

For Mirador de Gràcia, Masies de Mollet and La Nao, three Passivhaus care homes developed by FIATC Residencias, we designed specific training courses for the design and construction teams, including the architecture studio Genars, contractors Arnó, Cots i Claret, Tabicomplet and Grupo Alcúdia, site supervisors a3AT and installers Agefred and Eiffage. Each course looked in detail at the drawings, construction details and specifications of the thermal envelope and building services, presenting practical examples of Passivhaus construction for large and complex buildings, and looking at how to avoid mistakes and achieve certification on time, and on budget.

“I would especially like to highlight how useful this course was in bringing together everyone who is going to work on site: both designers, contractors and M & E installers!”

This was the feedback we got from the architectural technologist who took the training courses for the Mirador de Gràcia and Masies de Mollet care homes.

We’re committed to supporting teams who have their sights firmly set on high-performance, sustainable construction: a well-trained team that can prepare for, plan, and execute large and complex Passivhaus projects, is– above all- a team that will be cost effective.

What is the Passivhaus Planning Package (PHPP) and how can I use it to design high-performance buildings?

The Passivhaus Planning Package (PHPP) is an energy modelling and certification tool developed by the Passivhaus Institute in Germany. Used worldwide for the planning, design, and verification of Passivhaus buildings, the PHPP provides an accurate and accessible way for professionals to model energy performance.

What is the Passivhaus Planning Package (PHPP) and how can I use it to design high-performance buildings?

The Passivhaus Planning Package (PHPP) is an energy modelling and certification tool developed by the Passivhaus Institute in Germany. Used worldwide for the planning, design, and verification of Passivhaus buildings, the PHPP provides an accurate and accessible way for professionals to model energy performance and design high-performance buildings that meet the stringent energy efficiency standards of Passivhaus certification.

Programa de Planificación Passivhaus (PHPP)
Programa de Planificación Passivhaus (PHPP)

What is PHPP?

The PHPP is essentially a detailed spreadsheet-based tool designed for the calculation of energy balances in buildings. Unlike more complex dynamic simulation programs, the PHPP has been developed with simplicity and reliability in mind, making it approachable for construction professionals who may not be experts in thermodynamic modelling. This user-friendly design helps architects and designers verify compliance with the Passivhaus standard and optimize the energy balance of buildings by considering factors such as:

  • Thermal performance of the building envelope
  • Heating and cooling demand
  • Ventilation systems
  • Solar gains and shading
  • Domestic hot water and energy use

A notable aspect of the PHPP is that it has been developed and calibrated using DYNBIL, a thermodynamic simulation program created by Dr. Wolfgang Feist, founder of the Passivhaus Institute. DYNBIL in turn has been used extensively to model real-life buildings, whose results have been compared with measured data across multiple buildings, showing excellent correlation. This careful calibration ensures that PHPP results closely align with real-world building performance, offering reliability in energy modelling.

Key features and functions

  1. Accessibility for non-experts: one of the main goals of the PHPP has always been to make energy modelling accessible to construction professionals, particularly architects who may not have expertise in complex thermodynamic simulations. While tools such as DesignBuilder-EnergyPlus offer a vast array of high-resolution modelling capabilities, the abundance of input parameters can overwhelm inexperienced users and lead to significant inaccuracies. The PHPP counters this challenge by simplifying data entry, using reasonable default values that help ensure reliable outcomes.
  2. Simplified data input: the PHPP provides a streamlined approach to entering project data, making it easier for professionals to model building energy performance without needing to manage hundreds of intricate variables. This simplicity contributes to more consistent and accurate results.
  3. Reliable results & comprehensive analysis: the principle behind the PHPP is that “it’s better to be approximately right than precisely wrong.” By focusing on essential input parameters and calibrated default values, the tool minimizes the risk of errors that can occur in more complex simulation software. This reliability makes the PHPP an ideal choice for architects and builders tasked with delivering high-performance buildings that aiming for Passivhaus certification, based on a holistic approach that supports a thorough understanding of energy efficiency and helps guide design decisions.
  4. Energy demand calculations: PHPP helps estimate heating and cooling energy demands and peak loads, ensuring the building meets the Passivhaus standard of less than 15 kWh/m²·a for heating / cooling (the cooling requirement includes a variable for dehumidification), and less than 60 kWh/m2·a PER (Primary Energy Renewable).
  5. Airtightness assessment: the program incorporates calculations related to airtightness and allows the used to assess the impact of air permeability on the energy balance.
  6. Overheating & indoor humidity analysis: the tool provides an overheating analysis capability, with an in-built stress-test to determine whether a building without active cooling may suffer from overheating issues. The program also features an analysis of the risk of excessive indoor humidity, which can be a problem for thermal comfort in the summer and shoulder months.
  7. Climate data: while official PHI climate file should always be used in certification projects, users can input climate data specific to their project location, to compare results with the official climate files and ensure the energy modelling accurately reflects real-world conditions.
  8. Global Application: While designed in Germany, PHPP is adaptable to various climates and building types, making it a global standard for energy-efficient design.
  9. Verification for Certification: PHPP serves as the primary tool for Passivhaus building certification, verifying that the project complies with Passivhaus criteria.
  10. Energy balance optimization: it allows users to adjust building components and systems to optimize the building’s energy balance, including as insulation, thermal bridges, window frames and glazing, shading devices, thermal inertia, exterior colours, and mechanical and natural ventilation. Additionally, the tool provides easy modelling capabilities for a wide range of active systems: air-source / ground source / water source heat pumps, district heating/cooling systems, stoves and boilers, compact heat pump units, solar thermal systems, and solar photovoltaic generators.
  11. Comprehensive results: monthly and annual results are provided for useful energy demand, final energy demand, primary energy consumption and CO2 emissions, together with on-site renewable energy generation. Additionally, results are provided that indicate the % of hours (on a monthly basis) where overheating occurs and where there is excessive indoor humidity.
  12. Supports sustainability goals: By facilitating low-energy building designs, PHPP contributes to reduced carbon emissions and sustainable construction practices.
Programa de Planificación Passivhaus (PHPP)
Programa de Planificación Passivhaus (PHPP)

Why use PHPP for Passivhaus and high-performance projects?

Using PHPP is essential for any project aiming for Passivhaus certification because it ensures that the building design meets the energy efficiency thresholds required for the standard. This leads to:

  • Lower operational energy costs
  • Enhanced thermal comfort for occupants
  • Improved indoor air quality
  • Significant reductions in heating and cooling energy use

PHPP continues to evolve, incorporating new features and updates that respond to advances in building science and sustainability needs. Whether designing a residential home or a larger commercial project, PHPP provides the analytical backbone for realizing energy-efficient, comfortable, and environmentally friendly buildings.

Success in the 3rd Edition of our “Construction Verifier” Course: new students certified by the Passivhaus Institute

Success in the 3rd Edition of our “Construction Verifier” Course: new students certified by the Passivhaus Institute We are thrilled to announce that the students of the 3rd edition of our “Construction Verifier” course have successfully passed the official exam by the Passivhaus Institute, earning the Construction Verifier certification. After a month of intensive training, …

Success in the 3rd Edition of our “Construction Verifier” Course: new students certified by the Passivhaus Institute

We are thrilled to announce that the students of the 3rd edition of our “Construction Verifier” course have successfully passed the official exam by the Passivhaus Institute, earning the Construction Verifier certification.

3ª Edición del Curso Verificación de la Construcción
3ª Edición del Curso Verificación de la Construcción

After a month of intensive training, which included eight online sessions and a dedicated exam preparation day, the participants demonstrated their commitment and dedication by tackling a challenging test that ensures the highest quality standards in verifying Passivhaus projects.

This achievement reflects not only the effort of our students but also the practical and thorough approach of our training program. Throughout the course, participants gained advanced technical knowledge and developed essential skills to analyse, evaluate, and verify high performance construction projects.

3ª Edición del Curso Verificación de la Construcción. Foto Grupo Angel

The Construction Verifier certification is an internationally recognized qualification that attests to their ability to ensure that constructions meet the fundamental principles of the Passivhaus standard:

maximum energy efficiency, thermal comfort, and indoor air quality. With this certification, our students are ready to play a key role in driving the transition to more sustainable and high-performance construction.

We want to congratulate each of our students on this outstanding achievement. Their success not only enriches their professional careers but also strengthens the construction sector’s commitment to a more sustainable and efficient future.

Thanks also to the Passivhaus Institute for their support throughout the process. We will continue working to deliver excellence in training and to foster innovation in sustainable construction.

Congratulations to our new certified professionals!

Casa SG Magi: a deep energy retrofit in Sitges

Casa SG Magi: a deep energy retrofit in Sitges Casa SG Magi is an exemplary model of comprehensive energy renovation in Sitges, showcasing a strong commitment to sustainability and energy efficiency. Designed by Sergi Gargallo from SGArq Passivhaus Architecture, and certified by Oliver Style from Praxis Resilient Buildings, this single-family home, originally built in 1953, …

Casa SG Magi: a deep energy retrofit in Sitges

Casa SG Magi is an exemplary model of comprehensive energy renovation in Sitges, showcasing a strong commitment to sustainability and energy efficiency.

Designed by Sergi Gargallo from SGArq Passivhaus Architecture, and certified by Oliver Style from Praxis Resilient Buildings, this single-family home, originally built in 1953, has achieved the EnerPHit Plus certification. This recognition is a significant achievement, as it reduces the home’s energy consumption by 90%, turning it into a comfortable and efficient living space.

Casa SG Magi

Thermal envelope

The house is spread over two floors, with a useful floor area of 82 m². Casa SG Magi has undergone drastic surgery to maximize its energy efficiency. The external walls are fitted with an external thermal insulation system (ETICS) made of 120 mm of EPS, which eliminates thermal bridges and significantly reduces heat loss in the winter and heat gains in the summer. The roof is insulated with 200 mm of XPS insulation, while the floor slab has 10 cm of insulation, ensuring optimal thermal comfort. Unwanted air infiltration has been reduced to an extremely low level: n50 = 0.69 air changes per hour (ACH), compared to an existing home, which typically has an infiltration level of around n50 = 10 ACH.

High-Performance Windows

The windows of the house are another crucial aspect of its efficient design. The PVC WERU Afino One frames, certified as Passivhaus components, along with triple-glazed low-emissivity windows filled with argon gas, provide exceptional insulation. These features not only enhance energy efficiency but also increase interior comfort by reducing heat loss in winter and minimizing excessive heating in summer.

Casa SG Magi
Casa SG Magi

Mechanical Ventilation

To ensure optimal indoor air quality and prevent construction-related issues, Casa SG Magi is equipped with a Zehnder Comfoair Flex 250 sensible heat recovery unit. This controlled mechanical ventilation system removes odours and humidity, keeping the indoor air fresh and healthy.

Climate Control System

The home’s climate control is handled by an air-based system, consisting of two Panasonic CU-Z25UBEA air-to-air heat pumps, one on each floor, providing both heating and cooling. With a capacity of 2.5 kW for cooling and 3.2 kW for heating, these units ensure a comfortable environment year-round with minimal energy consumption.

Renewable Energy

One of the most impressive aspects of Casa SG Magi is its capacity to generate renewable energy. With the installation of 9 photovoltaic panels of 455 Wp, the house typically produces 32% more energy than it consumes. This not only makes it a self-sufficient home but also a small renewable energy generation center.

Casa SG Magi is an outstanding example of how energy renovation can transform a conventional house into a high-performance, energy-efficient home. Thanks to the vision of Sergi Gargallo and the certification by Oliver Style, this house in Sitges not only drastically reduces its energy consumption but also offers a healthy and comfortable indoor environment, contributing to the well-being of its occupants and the environment.

Photos: Juan Giribet de Sebastián

Casa SG Magi

Can Naiades: 15 steps towards a comfortable, healthy home, resilient, and efficient home

Can Naiades is a single-family, 4 bedroom, 2 storey Passivhaus Plus home, located in Sant Julia d’Alfou, Spain. Designed by Daniel Tigges from Tigges Architekt, and Praxis Resilient Buildings providing Passivhaus design.

Can Naiades: 15 steps towards a comfortable, healthy, resilient, and efficient home

Can Naiades is a single-family, 4 bedroom, 2 storey Passivhaus Plus home, located in Sant Julia d’Alfou, in the province of Barcelona, Catalonia, Spain. Designed by Daniel Tigges from Tigges Architekt, with Oftecnics as Quantity Surveyor/Site Supervisor, the house is built by House Habitat, with Fontalgar Instalaciones installing electrical and mechanical services, and Praxis Resilient Buildings providing Passivhaus design, HVAC system design and Blower Door testing. The house is being certified to Passivhaus standard by Micheel Wassouf of Energiehaus Arquitectos.

Can Naiades interior en construcción

1. Bioclimatic design

The house is built on a site that is sloped from east to west, with large stone retaining walls creating a platform where the house can sit with the longest façades aligned south / north. To maximise solar gain and daylighting, the windows on the southern façade make up 72% of the total window area, meaning that around 79% of the home’s heating requirements will be provided by the sun (14% will be provided by internal heat gains and the remaining 7% by the active heating system). Southern glazing is shaded in the summer by the balcony on the intermediate floor and a roof overhang, with external venetian blinds on all windows. The house has a relatively compact design with a heat loss form factor of 462 ÷ 128 = 3.6 (total envelope area ÷ treated floor area).

2. Geobiological survey

Early in the design process, a geobiological survey of the site was done by Architect Sonia Hernandez from the Arquitectura Sana, to measure electromagnetic radiation on the plot and identify possible sources of contamination. Low frequency electric and magnetic fields, high frequency electromagnetic fields, geological alterations, gamma and neutronic radiation, and terrestrial magnetic fields were measured. The results of the survey showed some terrestrial magnetic fields where beds were located in two of the first-floor bedrooms. The layout of the upstairs bedrooms was therefore modified to avoid potential health problems associated with long-term exposure. Another recommendation from the survey was to ensure that cabling in the bedrooms was shielded to avoid electromagnetic radiation while sleeping. As far as possible, low emission materials have been used to reduce indoor contaminants.

3. Timber structure

The house is built with a lightweight timber structure assembled off-site by EGOIN, in the Basque country (northern Spain), using local radiata pine timber. The wall modules consist of 140mm timber studs, filled with recycled glass wool insulation and enclosed internally with a 12mm particle board and externally with a 12mm OSB 3 board.

The roof modules consist of 200mm joists, filled with recycled glass wool insulation, enclosed internally with a dynamic vapour control membrane and externally with an 18mm OSB 3 board.

The intermediate floor and roof modules all came factory fitted with a SIGA Wetguard waterproof membrane, to protect them from rain during on-site assembly. Due the double height design in the sitting room area, a part of the structure on the northern façade consists of 150mm Cross Laminated Timber (CLT) panels, together with a steel frame structure.

The wall and roof modules were delivered to site and the house was erected and waterproofed in only 8 working days, bringing with it all the advantages of off-site prefabrication: rapid onsite assembly, greater precision and build quality, less waste, and optimization of materials.

4. Earthing system

A good earthing system is particularly important in timber houses, to avoid electromagnetic radiation from cables and appliances that can affect occupants’ health. To this end, four 3-meter cooper earth rods were installed, connected to an earth cable, in turn connected to the reinforced steel structure of the concrete floor slab. The reinforced steel structure itself was also welded at specific points to ensure a good electrical connection across the slab. The connections between copper and steel were sealed with a special paste to prevent galvanic corrosion and ensure a good earth connection for the working life of the building. A resistance to ground of ≤ 6 Ohms is recommended: once the earthing system was complete, the measured result was 2.15 Ω. Fantastic!

5. Thermal insulation

The walls and roof of Can Naiades are insulated with Knauf Insulation recycled glass wool insulation, chosen for fire resistance, good thermal performance and because they incorporate a bio-based E-Technology binder, free from added phenols and formaldehydes, protecting both the workers on site and future occupants from harmful emissions. The walls are insulated within the timber structure with 140mm, together with 60mm externally, and a further 50mm in the internal service void. The roof has 200mm of insulation between the timber structure, and a further 150mm on top. Between 100mm and 200mm of XPS insulation has been installed under the concrete floor slab. Supplied by Pafile, small amounts of aerogel- about the most insulating material there is for use in buildings- has been used to insulate specific sections of steel I-beams that were needed to reinforce the structure. Steel is a good heat conductor, so the aerogel blankets reduce thermal bridging, heat loss and cold spots where the steel penetrates the thermal envelope. 

6. Radon gas barrier

The floor slab is painted with a Soudatight liquid membrane made by Soudal, to form a radon gas barrier. This prevents the entrance of radon gas, which is naturally occurring, carcinogenic, invisible, and odourless, emitted from granitic rocks, and which can seep into building through floor slabs and walls to ground (for more information, see this article on radon gas).

7. Openings

The windows consist of triple glazed, argon-filled, low emissivity glazing and Passivhaus certified Smartwin timber-aluminium window frames made by Ventanas Gardea. Window thermal bridges are reduced to a minimum by insulating most of the fixed part of the frames. For the sills of the sliding and french windows, the frames are installed on an Isotop Winframer high density EPS board made by Iso Chemie, to reduce thermal bridging and cold spots. A FAKRO DEC quadruple-glazed roof light provides daylighting to the stairwell to the north. A Passivhaus certified airtight and insulated Petwalk cat flap will let the cat in and out with minimal heat loss.

8. Airtightness and vapour control

SIGA airtight tapes have been used for all the airtight sealing. A SIGA Majrex 200 dynamic membrane provides the air barrier and vapour control layer in the roof. The membrane has a variable vapour diffusion resistance, which means in winter it acts as a vapour barrier, and in summer, it lets vapour pass through. This protects the roof modules from the exfiltration of warm and humid air in the winter (important for avoiding interstitial condensation damage in flat non-ventilated timber roofs) and allows back drying in the summer (in case any humidity has accumulated during the winter, or due a water leak- whether during construction or in the future). A FINSA Superpan VapourStop particle board provides the air barrier and vapour control layer in the external walls. The house will undergo a whole-building Blower Door airtightness test, to meet the stringent Passivhaus requirement of n50 ≤ 0.6 ach. This means the equivalent total surface area of all the air leaks in the house will constitute a hole about 10cm x 10cm.

9. Ventilation

Clearly you can’t build an airtight, draught-free home without making sure the space is adequately ventilated, otherwise air quality would be terrible and there’d be way too much humidity in the indoor air. Added to this, every day, while we eat an average of 1kg of food and drink around 2 litres of water, we breath around 8000 litres of air. So reliable ventilation and good air quality are really important! In Can Naiades we’re using a Zehnder balanced whole-house mechanical ventilation system with heat recovery, that recovers around 90% of the heat from outgoing stale air and uses it to preheat incoming air. In the summer the heat recovery process is reversed, whereby incoming air is cooled by the relatively cooler outgoing stale air. If the outdoor air temperature is lower than the indoor temperature, an automatic bypass opens so that relatively cooler outdoor air is let in directly, providing “free cooling”.  In the entire process, the heat recovery unit consumes about the same amount of electricity as 2 low-energy light bulbs. The system blows pre-heated (or pre-cooled in the summer) fresh air into the bedrooms, sitting room and office, and extracts stale air from the kitchen and bathrooms, working 24 h/d, 365 days/year, silently and efficiently. The heat recovery unit includes a F7 filter on the incoming outdoor, removing pollutants in the outdoor air, which will mainly come from wood fires in the winter.

10. Keeping cool in the summer

Heat waves have been a feature of recent years, and are set to increase over the coming decades, so a series of design strategies have been implemented that will help keep the house cool, using very little energy. A balcony between the ground and first floor, together with the roof overhang, shade the southern glazing in the summer. All windows have Griesser Solomatic external venetian blinds, with slats that can be adjusted to let in natural light but block direct sunlight. The FAKRO roof light has an external awning to block solar gain, together with a motorised opening mechanism, which means it can be opened when it’s hot inside and cooler outside, drawing cool air in through the ground floor and 1st floor bedrooms and out through the roof light. The height difference provides higher air flow rates through what’s called the “stack” effect. The office and bedroom windows all have mosquito netting so then can be left tilted open at night, without bugs coming in. As in vernacular Mediterranean architecture, the house is rendered white on most of the façade, which means it reflects more sun in the summer and keeps cooler. 3 deciduous black poplar trees to the south and west of the house have been kept in place, to provide additional shading in the summer.

11. Heating & cooling

Comfort heating and cooling is provided by a Zehnder ComfoClime Q autonomous heat pump heating/cooling coil on the ventilation system. In heating mode, the heat pump extracts heat from the extract air and passes it to the supply air, heating it to up to 49ºC. In cooling mode, the unit extracts heat from the supply air and passes it to the extract air, cooling it down to 12ºC. This way, during most of the year, the heating and cooling needs of the home will be covered by the ventilation supply air, providing up to 3.8 kW of heating power and 1.7 kW of cooling power at a flow rate of 400 m3/h.

For peak cooling loads, a Panasonic Aquarea Ecoflex heat pump with a 7kW indoor ducted split unit, recirculates indoor air and removes heat from the building. Instead of dumping that heat to the outdoor air (as traditional air conditioners do) the Ecoflex recovers heat and transfers it the Domestic Hot Water (DHW) tank, thus reducing summer hot water energy consumption.

12. Domestic Hot Water (DHW)

The Panasonic Aquarea Ecoflex heat pump produces hot water for washing and showering, extracting heat from the outdoor air and transferring it to water in the DHW tank, moving- on average- 3.4 units of heat for every 1 unit of electricity (i.e. extremely efficient). As explained above, the heat pump has a heat recovery function when operating in cooling mode, where heat removed from the home is used to pre-heat hot water in the tank.  This increases the heat pump’s performance by around 52%, i.e. it moves 5.1 units of heat for every 1 unit of electricity. Alongside this, each shower is equipped with a Zypho drain water heat recovery system supplied by Aliaxis, using the heat from wastewater to preheat incoming cold water, reducing DHW energy consumption by between 30% and 50%. The hot water tank and the bathrooms have been located close enough to each other, to avoid the need for a DHW recirculation loop, avoiding the associated heat losses (which then become heat gains in the summer…).

13. Solar photovoltaic generation

Can Naiades will have 18 roof mounted solar PV panels (6,7 kWp in total) installed by Prot Energia, which’ll generate around 7000 kWh/a. This means the home, on an annual basis, will generate around 25% more electricity that it consumes.

14. Water saving

Saving energy is good but so is saving water. During the design phase there was a major drought in Catalonia, so the owners were clear that saving water was also a priority, given that droughts and heat waves are only set to increase over the coming decades. To this end, a series of water saving solutions have been included in the home, to radically reduce water consumption. First up, an Intewa grey water treatment system supplied by Ecospai takes wastewater from showers and sinks, cleans it, and pumps it back to toilet cisterns and to the washing machine. Secondly, low-flow shower heads and taps reduce water consumption. In the ground floor bathroom, there is a dry urinal, which precludes the need to use a flush toilet and saves around 4 litres of water that goes down the drain on each flush. Lastly, a rain catchment system collects water for garden watering. There will be no swimming pool, and the garden will include local Mediterranean plant species that don’t need much water.

15. Monitoring & control

The home will be monitored to track energy and water consumption using the Loxone control system, supplied by HEBHAUS, along with MICA indoor air quality sensors supplied by INBIOT and radon gas sensors supplied by Bequerel. Additionally, the Loxone system will be used to control blinds, outdoor lighting, a video intercom, a car charger and the heating, cooling and ventilation system.

The owners would like to thank all of the following people and companies for their support with the project:

We made it! Praxis Resilient Buildings achieves Passivhaus Classic Certification for Catalonia’s first certified care home!

Praxis Resilient Buildings is proud to announce the Passivhaus Classic certification of Mirador de Gracia, Catalonia’s first certified care home designed to meet rigorous energy efficiency standards.

We made it! Praxis Resilient Buildings achieves Passivhaus Classic Certification for Catalonia’s first certified care home!

Praxis Resilient Buildings logra la certificación Passivhaus Classic para la primera residencia de mayore

Mirador de Gracia: a groundbreaking Passivhaus certified care home in Barcelona

Praxis Resilient Buildings is proud to announce the Passivhaus Classic certification of Mirador de Gracia, Catalonia’s first certified care home designed to meet rigorous energy efficiency standards. Developed by FIATC Residencies and designed by Joaquim Rigau of GENARS, the building was certified by Micheel Wassouf of Energiehaus Arquitectos, with Oliver Style of Praxis Resilient Buildings delivering Passivhaus design, site supervision and preliminary blower door testing.

The Mirador de Gracia care home overlooks Barcelona from the Collserola hills, and is built on a challenging, sloped site. With a treated floor area of 4,600 square meters over eight floors, it includes 75 double rooms accommodating up to 143 residents, and additional facilities such as a gym, pharmacy, industrial kitchen and laundry, hair salon, seven day-rooms, and two roof gardens. The stunning sea views from this care home only add to its appeal, making it one of the most comfortable, low-energy, and draft-free residences of its kind in the region.

A new standard in comfort and energy savings

Mirador de Gracia exemplifies the potential of sustainable design for high-energy-demand buildings like care homes. With a 59 kWp roof-mounted solar photovoltaic array, this all-electric building generates around 26% of its annual energy consumption, contributing to significant operational and CO2 emission savings. Given that care homes are power hungry buildings- which require high standards of thermal comfort, 24/7 occupancy, and (in this particular case) daily production of around 469 meals—the building’s efficiency will translate into a projected 70% reduction in energy costs compared to traditional facilities.

Commitment to sustainable building

Achieving Passivhaus certification for Mirador de Gracia is the result of five years of dedicated work on Praxis’s most challenging and ambitious project to date. FIATC Residencies, the developer behind this project, is setting a new benchmark for energy-efficient care homes, with five more Passivhaus-certified facilities underway in Catalonia and Valencia. These efforts reflect a broader commitment to enhancing thermal comfort, reducing energy consumption, and cutting CO2 emissions—a triple win for residents, the environment, and operational savings.

As we continue our work on more Passivhaus care homes, this milestone represents a significant step forward in creating sustainable, high-performance buildings that prioritize both people and the planet.

Praxis Resilient Buildings Celebrates Double Win at Prestigious Awards

We’re very excited to have won two coveted industry awards, as a company recognized for its commitment to sustainable construction and resilience in architecture.

Praxis Resilient Buildings Celebrates Double Win at Prestigious Awards

We’re very excited to have won two coveted industry awards, as a company recognized for its commitment to sustainable construction and resilience in architecture. These honours not only reflect the company’s contributions to the construction and engineering sectors but also highlight its leadership in the industry’s ongoing transformation..

Praxis Resilient Buildings Celebrates Double Win at Prestigious Awards
BUILD Construction and Engineering Awards 2024

BUILD Construction and Engineering Awards 2024

At the forefront of the recognition is the BUILD Construction and Engineering Awards 2024, where Praxis Resilient Buildings was named a winner. Each year, the BUILD research and judging team carefully evaluates trailblazing companies that are shaping the construction and engineering industries. This year’s campaign examined all phases of the construction process—from design and planning to execution and maintenance. With construction representing over 13% of the global GDP and employing over 200 million people, Praxis Resilient Buildings’ achievements stand out as a reflection of the sector’s innovation and growth.

CEO Monthly’s Global CEO Excellence Awards

Additionally, Oliver Style, CEO of Praxis Resilient Buildings, was personally awarded “Most Dedicated Architecture & Engineering CEO 2024 (Spain)” by CEO Monthly in their Global CEO Excellence Awards. The awards spotlight CEOs who go above and beyond for their teams and industries. Style’s dedication to his company, combined with his leadership in sustainable construction, earned him this prestigious accolade.

Reflecting on the double win, Oliver Style commented:

“It is a great honour to receive these two awards from BUILD and CEO Monthly, and I thank both organizations. These awards are the result of a lot of hard work, and above all, teamwork, for which I’d like to personally thank Bega Clavero and Macarena Rossetti for their dedication and commitment. Lastly, we’d be nothing without our wonderful clients: a big thank you to them all for putting their trust in us and for daring to put sustainable construction at the heart of what they do.””

These awards are a testament to the innovation and resilience that underpin the work of Praxis Resilient Buildings, as we continue to push the boundaries of sustainable architecture and engineering in an ever-evolving industry..

CEO Monthly’s Global CEO Excellence Awards

Praxis qualifies as an airtightness testing laboratory for building quality control

Praxis has qualified as an airtightness testing laboratory for building quality control, an important recognition from the Spanish Ministry of Transport, Mobility and Urban Agenda

Praxis qualifies as an airtightness testing laboratory for building quality control

Praxis has qualified as an airtightness testing laboratory for building quality control, an important recognition from the Spanish Ministry of Transport, Mobility and Urban Agenda, confirming that Praxis is proficient in air leakage testing of buildings to ISO 9972:2019.

The Blower Door test is a widely used method for assessing the airtightness of buildings. This test is crucial for understanding how well a building envelope prevents unwanted air leakage, which directly impacts energy efficiency, indoor air quality, and overall comfort.

Praxis laboratorio de ensayo de hermeticidad para el control de calidad en la construcción
Praxis laboratorio de ensayo de hermeticidad

Praxis has also taken part in EILA

the inter-laboratory benchmarking program for Blower Door testing in Spain, run by the Instituto de Ciencias de la Construcción Eduardo Torroja (IETcc). As part of the program, Praxis undertook a Blower Door test in an apartment building in Barcelona city, with strict adherence to ISO 9972:2019.

Blower Door test ISO 9972: what is it?

The Blower Door test involves temporarily installing a powerful fan in the frame of an external door of the building. The fan either pressurizes or depressurizes the interior of the building, and sensors measure the rate at which air leaks through the building’s envelope. The test results are typically expressed as the air change rate per hour (ACH) at a specified pressure difference, typically 50 Pascals (Pa). This is known as the n50 value.

ISO 9972 provides a standardized methodology for performing the Blower Door test, ensuring consistency and accuracy across different buildings and testing conditions. This standard outlines the procedures for setting up the test, measuring air leakage, and reporting the results.

Praxis laboratorio de ensayo de hermeticidad
Praxis laboratorio de ensayo de hermeticidad

Airtightness testing: why is it useful?

  • Energy Efficiency: The Blower Door test identifies air leaks that can lead to significant energy loss. By locating and sealing these leaks, homeowners and builders can greatly reduce heating and cooling costs.
  • Building Performance: The test provides insight into the overall performance of the building’s envelope. High levels of airtightness indicate that the building is well-constructed and likely to provide better thermal comfort and energy efficiency.
  • Indoor Air Quality: Uncontrolled air leaks can bring in pollutants, moisture, and outdoor air contaminants. A well-sealed building ensures that ventilation systems work as intended, providing fresh air without the drawbacks of uncontrolled infiltration.
  • Compliance with Standards: Many building codes and green building certifications require a Blower Door test as part of the verification process. Achieving a low n50 value can be essential for meeting these standards and obtaining certifications like Passivhaus or LEED.
  • Comfort and Durability: Airtight buildings are generally more comfortable, as they prevent drafts and temperature fluctuations. Additionally, reducing air infiltration can help prevent moisture problems, which can lead to mould growth and structural damage.

Track record

In recent years, Praxis has undertaken blower door testing in hospitals, elderly people’s residences, office buildings, single family homes and multi-residential buildings, totalling 47,044 m2 of floor area..

We accompany our clients on site, providing technical advice and solutions for improving airtightness, for any kind of construction system or building typology.

Want to build tight?

Masies de Mollet & Mirador de Gracia achieve n50=0.6 ACH in their Final Blower Door Tests! 

Two recently completed care homes in Barcelona, now in the final stages of Passivhaus Certification, have reached an outstanding n50=0.6 ACH in their final Blower Door tests.

Masies de Mollet & Mirador de Gracia achieve n50=0.6 ACH in their Final Blower Door Tests!

Two recently completed care homes in Barcelona, now in the final stages of Passivhaus Certification, have reached an outstanding n50=0.6 ACH in their final Blower Door tests.

This remarkable achievement makes them the largest and most airtight buildings ever constructed in Catalonia! 

¡Las residencias Masies de Mollet & Mirador de Gracia logran n50=0,6 ren/h en sus ensayos finales de Blower Door!
Residencia Mirador de Gracia

Developed by FIATC Residencies and designed by Joaquim Rigau of GENARS, with Passivhaus design from Praxis

The two care homes Masies de Mollet and Mirador de Gracia are on the home straight for achieving Passivhaus Classic certification.

Thanks to a high-performance thermal envelope and highly efficient ventilation, heating, cooling and hot water systems, they will offer exceptional indoor air quality, superior thermal comfort, and projected savings of 70% in operational running costs compared to the owner’s other care homes. 

Blower Door test


A Blower Door test is used to assess a building’s air
permeability, helping to locate and seal air leaks and drafts.

Achieving a high level of airtightness is essential for Passivhaus buildings. The principle of “build tight, ventilate right!” helps reduce heat loss by up to 30%, while improving thermal and acoustic comfort, and maximizing the efficiency of mechanical ventilation, heating, and cooling systems. 





Mirador de Gracia

Floor area [m²]4595
Internal Volume [m³]13863
Building height [m]29
Infiltration rate @50 Pa q50 [m³/h]:8912
Infiltration air charge rate @50 Pa n500.6

Masies de Mollet

Floor area [m²]4566
Internal Volume [m³]15624
Building height [m]15
Infiltration rate @50 Pa q50 [m³/h]:9758
Infiltration air charge rate @50 Pa n500.6

In both the Mirador de Gracia and Mollet projects, Praxis played a key role in preparing the construction teams.

They delivered online Site Supervisor training to the design and construction teams before breaking ground. The courses covered the essential requirements for Passivhaus certification, including airtightness strategies, insulation specifications, thermal bridge-free detailing, and HVAC and DHW commissioning. 

On-site, Praxis conducted Passivhaus supervision and carried out preliminary Blower Door tests. Given the complexity of the buildings, the Mirador project required 10 preliminary tests—both partial and full—to identify leaks and seal them. The Mollet project underwent 6 preliminary tests before successfully passing the final assessment. Airtightness was achieved using gypsum plaster on exterior walls, reinforced concrete slabs for the ground floors and roofs, and windows sealed with tapes to the airtight layer, using Ampacoll Fenax tapes supplied by Ecospai. Service penetrations were sealed using flexible foam and airtight paint. A 1:1 full-scale mock-up was also built and tested, providing the construction teams valuable hands-on experience. 

After overcoming numerous challenges and a fair number of sleepless nights, the Praxis team, led by Oliver Style, celebrates this significant milestone in Passivhaus construction in Spain. Work continues on four more Passivhaus care homes for the same developer, all aiming for certification. Stay tuned! 

Residencia Masies de Mollet

Delivering large Passivhaus buildings: Site Supervisor & Construction Verifier training

Our experience with Site Supervisor and Construction Verifier training is that the courses provide architects and engineers with the tools they need for successful site supervision and navigation of the certification process, and deliver important on-site savings for developers and contractors. 

Delivering large Passivhaus buildings: Site Supervisor & Construction Verifier training

The article presents the experiences and lessons learned from our Passivhaus Site Supervisor and Construction Verifier training courses.

The courses provide architects and engineers with the tools they need for delivering large and complex Passivhaus buildings, achieving certification and reigning in cost overruns. 

Delivering large Passivhaus buildings
Photo: © Joan Giribet

Large and complex Passivhaus buildings: reducing risk and reigning in cost overruns through practical online training

“Your course has saved me at least 20,000 € in construction costs”

This was the feedback we got from the developer of a small multi-residential building we consulted on, following the online Site Supervisor course we gave to his team. The building was developed, designed, and built by a team with no prior experience in Passivhaus and has now achieved Passivhaus Classic certification.

Lack of experience increases the risk of cost overruns during the construction phase- particularly in relation to the execution of the airtight layer and achieving the required result in the final Blower Door test. Our experience with Site Supervisor and Construction Verifier training is that the courses provide architects and engineers with the tools they need for successful site supervision and navigation of the certification process, and deliver important on-site savings for developers and contractors. 

Using a Barcelona street advertising format to publicise the Site Supervisor course
Using a Barcelona street advertising format to publicise the Site Supervisor course
Using a Barcelona street advertising format to publicise the Construction Verifier course
Using a Barcelona street advertising format to publicise the Construction Verifier course

Another client, FIATC Residencias, who are developing 7 elderly people’s residencies that are all aiming for Passivhaus certification, have made our Site Supervisor and Construction Verifier course obligatory for the contractors, installers, and design teams on each project, with 3 courses held to date. In the course satisfaction survey, one student reported:

“I particularly want to highlight how useful it was to get all of us who’ll be working on-site together on the course, including both civil works and mechanical and electrical contractors”. 

Bridging the gap between Passivhaus design and Passivhaus construction: online Site Supervisor & Construction Verifier training

According to the PHI database, as of 2023, there were over 700 certified Passivhaus Designers in Spain and over 1300 Passivhaus Tradesperson, compared with 195 and 25 respectively in Germany. This suggests that Passivhaus design and tradesperson training has got off to a good start in the construction sector.

Praxis Resilient buildings

However, despite extensive Passivhaus Designer and Tradesperson training, there is a clear knowledge gap when it comes to the construction and certification of large and complex Passivhaus buildings. This is where the official Passivhaus Site Supervisor and Construction Verifier courses come in: they are especially designed to fill that gap, helping contractors, installers, site managers and tradespeople in the successful execution of large and complex Passivhaus buildings, on time, on budget, and compliant with Passivhaus certification. 

While the courses can be taken by any construction professional, those with Tradesperson and Designer qualifications can acquire the Site Supervisor or Construction Verifier add-ons, if they take the course and pass the exam (shown in Figure 2). At the time of writing, we have held two exams, leading to the first qualified Site Supervisors and Construction Verifiers in Spain. 

The format used for the courses and for the exam is 100 % online, making an easier fit with on-site work and other commitments. Exam preparation includes an intensive on-line class, with review of the course content and question and answer time. The Site Supervisor exam must be completed in under 45 minutes, and the Construction Verifier exam in under 2 hours, both done online. 

Praxis uses proprietary course material, based on abundant practical examples of on-site situations using photographs and videos. During each course, there are always two trainers, one giving the content and another attending the live chat, launching surveys, and posting references to documentation on the online campus, where 77 technical articles, guides and how-to documents are available for reading and download. A forum in the online campus provides a space for participants to ask questions, exchange ideas, and generate debate. The participants on our courses are often from very different countries and technical backgrounds, providing a rich and diverse learning environment.The Site Supervisor course consists of 4 modules, while the Construction Verifier course includes 8 modules, with the courses held concurrently.

Summary of the modules for each course and their content

CourseCourseModuleContent
Construction Verifier1Navigating Passivhaus Certification
Construction Verifier2Navigating Passivhaus Certification
Construction VerifierSite Supervisor3Insulation and thermal bridges
Construction VerifierSite Supervisor4Windows, doors and curtain walls
Construction VerifierSite Supervisor6Airtightness
Construction VerifierSite Supervisor6Mechanical & electrical services
Construction Verifier7Commissioning
Construction Verifier8Monitoring & performance verification

Every online session includes a guest speaker, presenting a specific technical issue relating to the module in question. Both during and at the end of each session, multiple choice questions are presented online to the students, to consolidate learning and generate debate and reflection. Each online session is also recorded and made available for watching offline, with attendees commenting that they found them to be a useful resource for reviewing and taking notes after the online classes. Additionally, and to provide networking opportunities, we offer site visits for all students, so they can see a Passivhaus building under construction in the month or two following the course.

Feedback

Each course includes on online student satisfaction survey. Some of the answers provide by students are shown below:

Filling the gap for a successful execution of large and complex Passivhaus buildings

Official Passivhaus Site Supervisor and Construction Verifier courses come in: they are especially designed to fill that gap, helping contractors, installers, site managers and tradespeople in the successful execution of large and complex Passivhaus buildings, on time, on budget, and compliant with Passivhaus certification. 

The growth in Passivhaus construction in Spain in recent years has been significant: in 2021, Spain was ranked 2nd in the world after China, with the most square meters of floor space certified to the Passivhaus standard. Increasingly, larger, and more complex Passivhaus buildings are being designed or retrofitted, tendered and built by large “mainstream” contractors and installers who often have little experience in executing Passivhaus buildings. The Site Supervisor and Construction Verifier courses provide contractors, installers, site managers and tradespeople with the knowledge they need for the successful execution of large and complex Passivhaus buildings.